It appears that the third film in the Narnia franchise is going south of the border instead of down under. According to Variety, The Chronicles of Narnia: The Voyage of the Dawn Treader will shoot a majority of the film in Mexico. The first two films - The Chronicles of Narnia: The Lion, The Witch and The Wardrobe and The Chronicles of Narnia: Prince Caspian were filmed mostly in New Zealand, due to government tax breaks and the fact that Weta, which created effects and props for the films, was based there.
The Michael Apted-directed The Chronicles of Narnia: The Voyage of the Dawn Treader's title refers to a large ship, which requires a immense water set piece that can be accommodated easier in Mexico. The film will be shot at Baja Studios in Rosarita, Mexico, where past nautical adventures like Titanic, Deep Blue Sea and Master and Commander: The Far Side of the World were all filmed.
While certain shots in Australia will still go on as planned, the move to shooting the bulk of the film in one location in Mexico will cut costs as well.
The film was supposed to start production in October, but now a January start date seems likely.